I&C System Analysis and Design

DOE-HDBK-6004-99

I&C System Analysis and Design

The design of the I&C systems should be integrated with the design of the facility systems (FS) to

account for both normal and off normal operation and to prevent or mitigate postulated accidents.

The integration of the facility systems and I&C system design functions should address:

1. the capability of I&C system to provide the proper measuring, detection, and control functions,

including adequate control and safety margins,

2. the necessary taps, ports, and penetrations to obtain the most desirable measurement parameters

for control and safety function actions,

3. a central control room with sufficient displays and command features to allow monitoring and

response to all accident Postulated Initiating Events (PIE), except those that are highly unlikely,

4. automatic initiation of all safety function actuations which are not assigned to the operator,

5. feedback from control function actions to determine the effect on the process,

6. a system of interlocks and permissives to reduce the likelihood of erroneous operator action,

7. a system of controlled by-passes to permit deliberate operator action in abnormal unanticipated

situations,

8. manual initiation and control for safety function actions not appropriate for automatic initiation

or for chosen automatic action interruption or adjustment capabilities.

Control System

Basic Control systems should be designed with sufficient margin to ensure that the design conditions

are not exceeded, during any condition of normal operation including anticipated operational

occurrences and transients.

The Basic Control System should be capable of maintaining the normal operating parameters and

should provide all operator interface (indication, alarm, and data collection), during normal operation

and anticipated operational occurrences and transients that may be created by postulated initiating

events. A Task Analysis should be conducted to determine which control functions are to be assigned

to the operator and which functions are to be machine (automatic action) assigned.

The control system design should provide for operator control and monitoring of essential facility

systems in a central control room. The control room, as well as supporting I&C system local control

and monitoring panels, should be designed for man/machine interface and local area or room

habitability considerations. This design should consider control and monitoring functions for conduct

of operations under both normal operation and postulated accident scenarios.